Straight bevel gears are used for many automotive applications, such as differential gearing. Currently, gear manufacturers employ a number of various method for making gears. Recently, forging technology has achieved tremendous development and become very popular. Compared to machining, forging has its advantages of improving the product quality by achieving a high stiffness in the material without cutting the material flow lines, good surface condition at the formed part, and work hardening that increases wear resistance, and quick cycle time suitable for mass production.
Forging die design is essential for the manufacturing of the gear because it determines the shape of the gear and, therefore, performance of the gearing incorporating this gear. Currently, forging dies for straight bevel gears are generated by a gear cutter. Thus, root area of the straight bevel gear is determined by the cutter edge radius. The current method of making the gear cutter is not optimizes a cutter edge radius, which creates stress concentration in a gear root area.